User Interface Task

User Interface control task.

This task controls the user interface of the Reader. User Interface of the Reader RevA board consists of 2 bi-color (red/green) LEDs, labelled Status LED and Lock LED and of a small speaker. This UI can use a combination of flashes and beeps to inform the user of a certain state or of an event.

The UI has 2 ways of informing the user of something: persistent states and message flashes. The persistent state informs user of some long-lasting condition (like system OK, door locked). The persistent state stays the same and displayed until it is explicitly changed. The message flashes are used to inform the user of one-time events that just happened (card rejected). They will execute a scripted sequence and then automatically return to previous persistent state.

Example: The system starts the UI task, which switches to the default state (Error). The system initializes a connection with the Controller and switches the task to “Normal - Locked” state. A user attempts to open the door using an invalid card. The persistent state stays “Normal - Locked” and “Card Rejected” UI flash will play. The user uses a correct card. The persistent state changes to “Normal - Unlocked” and on top of that “Card Accepted” UI flash will play.

Note

Deciding when to unlock and lock the door again is responsibility of the Controller, so even though the door is usually unlocked only temporarily, “Normal - Unlocked” is a persistent state from the Reader’s point of view.

Enums

enum dl_task_ui_state

User interface states.

These are persistent states which the user interface may be presenting to the User. User is in a given state until it is explicitly changed.

Values:

DL_TASK_UI_STATE_ERROR

Error state. Status LED is blinking red. This is the default

DL_TASK_UI_STATE_LOCKED

Normal locked. Status LED is green, Lock led is red

DL_TASK_UI_STATE_UNLOCKED

Normal unlocked. Status LED is green, lock led is green

enum dl_task_ui_flash

User interface flashes.

These are temporary user interface states. They are usually a sequence of actions (a beep, LED blink) displayed on top of the persistent state until the sequence finishes.

Example: UI state is DL_TASK_UI_STATE_UNLOCKED, and flash DL_TASK_UI_FLASH_READ_OK is invoked. This flash will beep once with a high tone and then stop. UI stays in the DL_TASK_UI_STATE_UNLOCKED.

Values:

DL_TASK_UI_FLASH_READ_OK

Card read and auth OK: One long high-pitched beep

DL_TASK_UI_FLASH_READ_BAD

Card read and auth failed: Three short low-pitched beeps

DL_TASK_UI_FLASH_VADER

Vader

Functions

void dlTaskUiInit(uint8_t task_id, dl_task_ui_callbacks *callbacks)

Task initializer.

This function initalizes internal data structure of the task and sets up callbacks to the Master Task

Parameters

• task_id: Our identificator the Master Task has chosen
• callbacks: Structure of function pointers to callbacks this task should use

void dlTaskUiStart(void)

Task starter.

This function starts the task thread.

void dlTaskUiStop(void)

Task stopper.

This function stops the task thread.

void dlTaskUiSetUIState(dl_task_ui_state state)

Sets the persistent UI state.

Note

Thread safety: This function can be called from any thread when the ChibiOS is in Normal state.

Parameters

• dl_task_ui_state: UI state to set

void dlTaskUiFlashMessage(dl_task_ui_flash flash)

Flashes a temporary user state.

Note

Thread safety: This function can be called from any thread when the ChibiOS is in Normal state.

Parameters

• dl_task_ui_flash: UI flash

struct dl_task_ui_callbacks

#include <ui-task.h>

A structure of Master Task callbacks.

User Interface of the Reader has no input elements, so this task does not need to report anything else than heartbeat to the Master Task.

Note

These callbacks must be thread safe

Public Members

void (*heartbeat)(uint8_t task_id)

A heartbeat callback.

A Heartbeat callback of the Master Task. See firmware documentation, section “Reader Firmware Architecture”, subsection “Watchdog”

Parameters

• task_id: ID of this task, assigned to us by the Master Task